$str =~ s/((^|\n| |\t)(?: |\t|(?<! |\t)\n)*)/$2/gs;

[download]

fixes most cases but doesn't convert a tab to a space if it is the first character in a white space string of characters.

Perl reduces RSI - it saves typing

In reply to Re: removing redundantwhitespace by GrandFather
in thread removing redundantwhitespace by Anonymous Monk

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